CN116674556B - Vehicle drift control method and device, vehicle and medium - Google Patents

Vehicle drift control method and device, vehicle and medium Download PDF

Info

Publication number
CN116674556B
CN116674556B CN202310923166.XA CN202310923166A CN116674556B CN 116674556 B CN116674556 B CN 116674556B CN 202310923166 A CN202310923166 A CN 202310923166A CN 116674556 B CN116674556 B CN 116674556B
Authority
CN
China
Prior art keywords
vehicle
drift
torque
rear wheel
vehicle speed
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202310923166.XA
Other languages
Chinese (zh)
Other versions
CN116674556A (en
Inventor
冯茂林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xiaomi Automobile Technology Co Ltd
Original Assignee
Xiaomi Automobile Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xiaomi Automobile Technology Co Ltd filed Critical Xiaomi Automobile Technology Co Ltd
Priority to CN202310923166.XA priority Critical patent/CN116674556B/en
Publication of CN116674556A publication Critical patent/CN116674556A/en
Application granted granted Critical
Publication of CN116674556B publication Critical patent/CN116674556B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W30/00—Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
    • B60W30/18—Propelling the vehicle
    • B60W30/18009—Propelling the vehicle related to particular drive situations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
    • B60W10/04—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units
    • B60W10/08—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units including control of electric propulsion units, e.g. motors or generators
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/10—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to vehicle motion
    • B60W40/105—Speed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W2710/00—Output or target parameters relating to a particular sub-units
    • B60W2710/08—Electric propulsion units
    • B60W2710/083—Torque
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/72—Electric energy management in electromobility

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Electric Propulsion And Braking For Vehicles (AREA)

Abstract

The disclosure relates to a vehicle drift control method, device, vehicle and medium in the technical field of vehicle control, so as to solve the problems of unreasonable torque control of a rear wheel driving motor and vehicle drift failure, comprising the following steps: under the condition that the vehicle is in a vehicle drifting mode, acquiring a drifting parameter value of the vehicle; determining a reference vehicle speed of the vehicle according to the drift parameter value; if the reference vehicle speed is smaller than a preset vehicle speed threshold value, limiting the request torque of the rear wheel driving motor according to the reference maximum torque; if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, determining the request torque of the rear wheel driving motor according to the slip rate; and controlling the torque of the rear wheel drive motor according to the request torque so as to enable the vehicle to drift. Therefore, the probability of successful drifting of the vehicle is improved on the basis of ensuring the drifting safety of the vehicle.

Description

Vehicle drift control method and device, vehicle and medium
Technical Field
The disclosure relates to the technical field of vehicle control, and in particular relates to a vehicle drift control method, a vehicle drift control device, a vehicle and a medium.
Background
The vehicle drift mode typically requires the ESP (Electronic Stability Program, electronic body stabilization system) to be turned off to shut down the TCS (Traction Control System ) and VDC (Vehicle Dynamics Controller, vehicle dynamics controller) to give the vehicle full control to the driver, avoiding system intervention, and thus vehicle drift typically depends on the driver's joint operation of throttle, steering, braking, etc., which is unskilled, which can easily lead to vehicle drift failure.
Disclosure of Invention
In order to overcome the problems in the related art, the present disclosure provides a vehicle drift control method, device, vehicle and medium.
According to a first aspect of an embodiment of the present disclosure, there is provided a vehicle drift control method including:
under the condition that the vehicle is in a vehicle drifting mode, acquiring a drifting parameter value of the vehicle;
determining a reference vehicle speed of the vehicle according to the drift parameter value;
if the reference vehicle speed is smaller than a preset vehicle speed threshold value, limiting the request torque of the rear wheel driving motor according to the reference maximum torque;
if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, determining the request torque of the rear wheel driving motor according to the slip rate;
And controlling the torque of the rear wheel drive motor according to the request torque so as to enable the vehicle to drift.
Optionally, the slip ratio includes a target slip ratio and an actual slip ratio, and if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold, determining the requested torque of the rear wheel driving motor according to the slip ratio includes:
if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, inquiring to obtain the target slip rate according to the reference vehicle speed;
determining the actual slip rate according to the reference vehicle speed and the rear wheel speed in the drift parameter value;
and under the condition that the magnitude relation between the target slip rate and the actual slip rate does not meet a preset drift condition, reducing the request torque of a rear wheel driving motor of the vehicle until the magnitude relation between the target slip rate and the actual slip rate meets the preset drift condition.
Optionally, the reducing the request torque of the rear wheel driving motor of the vehicle in the case that the magnitude relation between the target slip rate and the actual slip rate is determined not to meet a preset drift condition includes:
determining a slip ratio difference value between the actual slip ratio and the target slip ratio under the condition that the magnitude relation between the target slip ratio and the actual slip ratio does not meet a preset drift condition;
Determining a torque reduction gradient according to a preset proportionality coefficient and the slip ratio difference value;
and reducing the request torque of the rear wheel driving motor according to the torque reduction gradient and the current output torque of the rear wheel driving motor.
Optionally, if the reference vehicle speed is smaller than a preset vehicle speed threshold, limiting the request torque of the rear wheel driving motor according to the reference maximum torque includes:
if the reference vehicle speed is smaller than a preset vehicle speed threshold value, determining a reference maximum torque according to a ground attachment coefficient, the whole vehicle mass and the rolling radius of the vehicle tyre;
in the case where the requested torque of the rear wheel drive motor is greater than the reference maximum torque, the requested torque of the rear wheel drive motor of the vehicle is limited with the reference maximum torque.
Optionally, the drift parameter value includes a front wheel speed, and the determining the reference vehicle speed of the vehicle according to the drift parameter value includes:
and determining the reference speed of the vehicle according to the average value of the front wheel speeds.
Optionally, the vehicle drift control method includes:
if the vehicle is determined to have drift out of control in the vehicle drifting process, determining a target vehicle body slip angle and a braking force coefficient of the vehicle according to the reference vehicle speed;
Determining a target braking force according to the braking force coefficient, the difference value of the target vehicle body slip angle and the current vehicle body slip angle of the vehicle;
and applying the target braking force to a target wheel of the vehicle until the current body slip angle of the vehicle is less than or equal to the target body slip angle, wherein the target wheel is a front wheel of the vehicle which is positioned outside a drifting direction and a rear wheel which is positioned outside the drifting direction.
Optionally, the vehicle is determined to have drift out of control by:
acquiring a current body slip angle of the vehicle body;
inquiring a target vehicle body limit slip angle from a vehicle body slip angle mapping table according to the reference vehicle speed, wherein the vehicle body limit slip angle corresponding to each reference vehicle speed is stored in the vehicle body slip angle mapping table;
and under the condition that the current body slip angle of the vehicle body is larger than the target body limit slip angle, determining that the vehicle is out of control in drift.
Optionally, the vehicle is determined to have drift out of control by:
acquiring the current rotation direction and rotation angle of the steering wheel of the vehicle;
determining a current steering wheel limit angle of the vehicle under the condition that the rotation direction is inconsistent with the drifting direction;
And under the condition that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift.
Optionally, the vehicle drift control method includes:
acquiring driver monitoring information from a driver monitoring system;
and under the condition that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift, comprising the following steps:
and determining that the vehicle is out of control in drift under the conditions that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range, the yaw rate of the vehicle is continuously increased, and the driver monitoring information indicates that the driver is in a driving confusion state.
According to a second aspect of the embodiments of the present disclosure, there is provided a vehicle drift control device including:
an acquisition module configured to acquire a drift parameter value of the vehicle in a case where the vehicle is in a vehicle drift mode;
a first determination module configured to determine a reference vehicle speed of the vehicle based on the drift parameter value;
A second determining module configured to limit the requested torque of the rear wheel drive motor according to the reference maximum torque if the reference vehicle speed is less than a preset vehicle speed threshold; if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, determining the request torque of the rear wheel driving motor according to the slip rate;
a control module configured to torque control the rear wheel drive motor in accordance with the requested torque to enable the vehicle to drift.
Optionally, the slip ratio includes a target slip ratio and an actual slip ratio, and the second determining module is configured to:
if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, inquiring to obtain the target slip rate according to the reference vehicle speed;
determining the actual slip rate according to the reference vehicle speed and the rear wheel speed in the drift parameter value;
and under the condition that the magnitude relation between the target slip rate and the actual slip rate does not meet a preset drift condition, reducing the request torque of a rear wheel driving motor of the vehicle until the magnitude relation between the target slip rate and the actual slip rate meets the preset drift condition.
Optionally, the second determining module is configured to:
determining a slip ratio difference value between the actual slip ratio and the target slip ratio under the condition that the magnitude relation between the target slip ratio and the actual slip ratio does not meet a preset drift condition;
determining a torque reduction gradient according to a preset proportionality coefficient and the slip ratio difference value;
and reducing the request torque of the rear wheel driving motor according to the torque reduction gradient and the current output torque of the rear wheel driving motor.
Optionally, the second determining module is configured to:
if the reference vehicle speed is smaller than a preset vehicle speed threshold value, determining a reference maximum torque according to a ground attachment coefficient, the whole vehicle mass and the rolling radius of the vehicle tyre;
in the case where the requested torque of the rear wheel drive motor is greater than the reference maximum torque, the requested torque of the rear wheel drive motor of the vehicle is limited with the reference maximum torque.
Optionally, the drift parameter value includes a front wheel speed, and the first determining module is configured to:
and determining the reference speed of the vehicle according to the average value of the front wheel speeds.
Optionally, the vehicle drift control device includes: a runaway control module configured to:
If the vehicle is determined to have drift out of control in the vehicle drifting process, determining a target vehicle body slip angle and a braking force coefficient of the vehicle according to the reference vehicle speed;
determining a target braking force according to the braking force coefficient, the difference value of the target vehicle body slip angle and the current vehicle body slip angle of the vehicle;
and applying the target braking force to a target wheel of the vehicle until the current body slip angle of the vehicle is less than or equal to the target body slip angle, wherein the target wheel is a front wheel of the vehicle which is positioned outside a drifting direction and a rear wheel which is positioned outside the drifting direction.
Optionally, the runaway control module is configured to determine that the vehicle is out of drift by:
acquiring a current body slip angle of the vehicle body;
inquiring a target vehicle body limit slip angle from a vehicle body slip angle mapping table according to the reference vehicle speed, wherein the vehicle body limit slip angle corresponding to each reference vehicle speed is stored in the vehicle body slip angle mapping table;
and under the condition that the current body slip angle of the vehicle body is larger than the target body limit slip angle, determining that the vehicle is out of control in drift.
Optionally, the runaway control module is configured to determine that the vehicle is out of drift by:
acquiring the current rotation direction and rotation angle of the steering wheel of the vehicle;
determining a current steering wheel limit angle of the vehicle under the condition that the rotation direction is inconsistent with the drifting direction;
and under the condition that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift.
Optionally, the vehicle drift control device includes: a second acquisition module configured to acquire driver monitoring information from the driver monitoring system;
the out-of-control module is configured to determine that the vehicle is out of control in drift when a difference between the steering wheel limit rotation angle and the rotation angle is within a preset difference range, the yaw rate of the vehicle is continuously increasing, and the driver monitoring information indicates that the driver is in a driving confusion state.
According to a third aspect of embodiments of the present disclosure, there is provided a vehicle comprising:
a processor;
A memory for storing processor-executable instructions;
wherein the processor is configured to execute the executable instructions stored by the memory to implement the vehicle drift control method of any one of the first aspects.
According to a fourth aspect of embodiments of the present disclosure, there is provided a computer readable storage medium having stored thereon computer program instructions which, when executed by a processor, implement the steps of the vehicle drift control method of any of the first aspects.
The technical scheme provided by the embodiment of the disclosure can comprise the following beneficial effects:
under the condition that the vehicle is in a vehicle drifting mode, acquiring a drifting parameter value of the vehicle; determining a reference vehicle speed of the vehicle according to the drift parameter value; if the reference vehicle speed is smaller than the preset vehicle speed threshold value, limiting the request torque of the rear wheel driving motor according to the reference maximum torque, and avoiding the excessive request torque input, too large rear wheel driving motor torque and instantaneous break of the grip limit of the rear wheel, so that the tail of the vehicle is out of control; if the reference vehicle speed is greater than or equal to a preset vehicle speed threshold value, determining the request torque of the rear wheel driving motor according to the slip rate, and reducing the risk of out-of-control vehicle drift; the rear wheel drive motor is torque controlled in accordance with the requested torque to enable the vehicle to drift. Therefore, the probability of successful drifting of the vehicle is improved on the basis of ensuring the drifting safety of the vehicle.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure.
Fig. 1 is a flowchart illustrating a vehicle drift control method according to an exemplary embodiment.
Fig. 2 is a flow chart illustrating one implementation of step S14 of fig. 1, according to an exemplary embodiment.
Fig. 3 is a flow chart illustrating one implementation of step S13 in fig. 1 according to an exemplary embodiment.
FIG. 4 is a flowchart illustrating a drift control vehicle body correction method, according to an exemplary embodiment.
FIG. 5 is a schematic diagram illustrating a vehicle drift according to an exemplary embodiment.
Fig. 6 is a block diagram illustrating a vehicle drift control device according to an exemplary embodiment.
FIG. 7 is a functional block diagram of a vehicle shown in an exemplary embodiment.
Detailed Description
Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present disclosure as detailed in the accompanying claims.
It should be noted that, all actions of acquiring signals, information or data in the present application are performed under the condition of conforming to the corresponding data protection rule policy of the country of the location and obtaining the authorization given by the owner of the corresponding device.
The inventor finds that in the drifting process of the vehicle, if the accelerator input is too large, the torque provided by the rear wheel motor is too large, the rear wheel instantaneously breaks through the grip limit of the tire, the tail of the vehicle is easy to run out, the vehicle is turned over, and the safety is influenced.
In view of the above, the application provides a vehicle drift control method, which aims to prevent the vehicle from turning over and affecting the safety of the vehicle due to out-of-control of the tail of the vehicle caused by overlarge throttle input. And, the request torque of rear wheel driving motor is controlled by the slip rate, has reduced the driver and controlled the risk that vehicle drift is out of control.
Fig. 1 is a flowchart of a vehicle drift control method according to an exemplary embodiment, as shown in fig. 1, including the following steps.
In step S11, in the case where the vehicle is in the vehicle drift mode, a drift parameter value of the vehicle is acquired.
In an embodiment of the present disclosure, the vehicle being in the vehicle drift mode may be a driving condition that turns off the vehicle ESP, TCS, VDC and ABS (antilock brake system).
The drift parameter values can be parameter values collected by sensors such as an inertial measurement sensor and a wheel speed sensor, wherein the sensors are arranged at different positions of the vehicle and are unified sensor parameter values, and under the condition that the parameter values collected by the sensors are determined to be effective, the parameter values collected by the sensors can be subjected to signal filtering and coordinate conversion by taking the mass center of the vehicle as a reference to obtain the parameter values under the same coordinate.
In step S12, a reference vehicle speed of the vehicle is determined based on the drift parameter value.
In the embodiment of the disclosure, the reference vehicle speed of the vehicle may be determined according to one of the wheel speeds of the plurality of wheels in the drift parameter value, or the average value of the wheel speeds of the plurality of wheels. For example, the reference vehicle speed of the vehicle is determined based on the wheel speed of the left front wheel or the wheel speed of the right front wheel in the drift parameter value.
In step S13, if the reference vehicle speed is smaller than the preset vehicle speed threshold, the requested torque of the rear wheel drive motor is limited according to the reference maximum torque.
In the embodiment of the disclosure, the preset vehicle speed threshold value can be set to be 10 km/h, under the condition that the reference vehicle speed of the vehicle is smaller than 10kph, the vehicle is in a steady state round, the large accelerator inputs the request torque of the rear wheel driving motor, the torque of the rear wheel driving motor is rapidly increased until the rear wheel breaks through the ground grabbing force limit, and in the vehicle drifting process, the request torque of the rear wheel driving motor is limited according to the reference maximum torque, so that the vehicle drifting posture is controlled.
It can be stated that the vehicle drift control can be divided into reference maximum torque control and slip rate control according to the magnitude relation between the reference vehicle speed and the preset vehicle speed threshold, if the slip rate is used for closed loop control in the vehicle drift or drifting process, under the condition that the deviation between the actual slip rate and the target slip rate is large, the request torque of the rear wheel driving motor is smaller than the large accelerator rapid accelerator pedal torque threshold, the torque of the rear wheel driving motor is rapidly increased, the request torque of the rear wheel driving motor is larger than the large accelerator rapid accelerator pedal torque threshold, the rear wheel driving motor can be excessively reduced, the vehicle speed is rapidly reduced to 0, and the drift fails, so that the request torque of the rear wheel driving motor is limited by the reference maximum torque when the reference vehicle speed is smaller than 10 kph. That is, in the case where the requested torque of the rear wheel drive motor is equal to or less than the reference maximum torque, the rear wheel drive motor is controlled with the requested torque of the rear wheel drive motor; in the case where the requested torque of the rear wheel drive motor is greater than the reference maximum torque, the rear wheel drive motor is controlled with the reference maximum torque. Therefore, the problem that the vehicle is turned over and the safety of the vehicle is affected due to the fact that the tail of the vehicle is thrown out of control due to the fact that the throttle input is too large is avoided.
In step S14, if the reference vehicle speed is equal to or greater than the preset vehicle speed threshold, the requested torque of the rear wheel drive motor is determined according to the slip ratio.
The method comprises the steps of determining the required torque of a rear wheel driving motor according to the slip rate, determining whether the reference vehicle speed is greater than or equal to a preset vehicle speed threshold value or not after adjusting the required torque of the rear wheel driving motor each time, and further continuing closed-loop control.
When the drift radius is increased, the reference vehicle speed is increased to 10kph or more, and the requested torque slip ratio of the rear wheel drive motor is controlled.
In step S15, torque control is performed on the rear wheel drive motor according to the requested torque so that the vehicle can achieve drifting.
It will be appreciated that during vehicle drift, the front wheels are subject to little or no driving force, and therefore only the rear wheel drive motors corresponding to the rear wheels need to be torque controlled to effect vehicle drift.
According to the technical scheme, under the condition that the vehicle is in the vehicle drifting mode, the drifting parameter value of the vehicle is obtained; determining a reference vehicle speed of the vehicle according to the drift parameter value; if the reference vehicle speed is smaller than the preset vehicle speed threshold value, limiting the request torque of the rear wheel driving motor according to the reference maximum torque, and avoiding the excessive request torque input, too large rear wheel driving motor torque and instantaneous break of the grip limit of the rear wheel, so that the tail of the vehicle is out of control; if the reference vehicle speed is greater than or equal to a preset vehicle speed threshold value, determining the request torque of the rear wheel driving motor according to the slip rate, and reducing the risk of out-of-control vehicle drift; the rear wheel drive motor is torque controlled in accordance with the requested torque to enable the vehicle to drift. Therefore, the probability of successful drifting of the vehicle is improved on the basis of ensuring the drifting safety of the vehicle.
Optionally, the slip ratio includes a target slip ratio and an actual slip ratio, and fig. 2 is a flowchart illustrating an implementation of step S14 in fig. 1 according to an exemplary embodiment, as shown in fig. 2, in step S14, if the reference vehicle speed is greater than or equal to a preset vehicle speed threshold, determining the requested torque of the rear wheel driving motor according to the slip ratio includes:
in step S141, if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold, the target slip ratio is obtained according to the reference vehicle speed.
The one-to-one correspondence between the reference vehicle speed and the slip ratio can be established in advance, and then the corresponding slip ratio is inquired as the target slip ratio according to the reference vehicle speed in an inquiry mode.
In step S142, the actual slip ratio is determined based on the reference vehicle speed and the rear wheel speed in the drift parameter value.
In the embodiment of the disclosure, the actual slip ratio is determined by the following calculation formula:
actual slip ratio= (rear axle shaft speed-reference vehicle speed)/reference vehicle speed
The calculation formula directly subtracts the rear axle speed from the reference vehicle speed in value, and divides the reference vehicle speed to obtain the actual slip rate. The rear axle speed is calculated from the wheel speed of the rear wheels, for example, by converting the average value of the wheel speeds of the rear wheels into a centroid speed relative to the centroid of the vehicle, and taking the centroid speed as the rear axle speed.
In step S143, in the case where it is determined that the magnitude relation between the target slip ratio and the actual slip ratio does not satisfy the preset drift condition, the requested torque of the rear wheel drive motor of the vehicle is reduced until the magnitude relation between the target slip ratio and the actual slip ratio satisfies the preset drift condition.
In one embodiment, the preset drift condition may be that the actual slip rate is greater than the target slip rate, and if the magnitude relation between the target slip rate and the actual slip rate indicates that the actual slip rate is greater than the target slip rate, the requested torque of the rear wheel drive motor of the vehicle is reduced. The actual slip ratio is less than or equal to the target slip ratio until the requested torque of the rear wheel drive motor of the vehicle is reduced.
In another embodiment, the preset drift condition may be that a slip ratio difference between the actual slip ratio and the target slip ratio is greater than a preset slip ratio difference threshold. And if the magnitude relation between the target slip rate and the actual slip rate represents that the slip rate difference between the actual slip rate and the target slip rate is larger than the preset slip rate difference threshold value, reducing the request torque of the rear wheel driving motor of the vehicle. And until the required torque of the rear wheel driving motor of the vehicle is reduced, the slip rate difference value between the actual slip rate and the target slip rate is smaller than or equal to a preset slip rate difference threshold value.
Thus, after the driver operates the large throttle, the large throttle is automatically controlled according to the target slip rate and the actual slip rate, and the risk of the driver controlling the vehicle to be out of control is reduced.
Optionally, in step S143, in a case where it is determined that the magnitude relation of the target slip ratio and the actual slip ratio does not satisfy the preset drift condition, reducing the requested torque of the rear wheel drive motor of the vehicle includes:
and under the condition that the magnitude relation between the target slip rate and the actual slip rate does not meet the preset drift condition, determining a slip rate difference value between the actual slip rate and the target slip rate.
In the embodiment of the disclosure, under the condition that the preset drift condition is that the actual slip rate is greater than the target slip rate, determining a slip rate difference value between the actual slip rate and the target slip rate; under the condition that the slip ratio difference value between the actual slip ratio and the target slip ratio is larger than the preset slip ratio difference value threshold value, the slip ratio difference value obtained by the previous steps is calculated, and the slip ratio difference value can be directly obtained without repeated calculation.
And determining a torque reduction gradient according to the preset proportionality coefficient and the slip ratio difference value.
In the embodiment of the disclosure, the product of the preset proportional coefficient and the slip ratio difference value in value is determined as the value of the torque reduction gradient.
And reducing the request torque of the rear wheel drive motor according to the torque reduction gradient and the current output torque of the rear wheel drive motor.
In the disclosed embodiment, the sum of the torque reduction gradient and the current output torque of the rear wheel drive motor is used as the request torque for controlling the rear wheel drive motor for a new wheel.
For example, the requested torque for controlling the rear wheel drive motor for a new round may be determined by the following calculation process:
△Slip=Slip–SlipTar
TorqueRequest=P×△Slip+Torqueinit
wherein P is a preset proportionality coefficient, torqueinit is the current output torque of the rear wheel drive motor, slip is the actual Slip rate, slip is the target Slip rate, delta Slip is the Slip rate difference, and TorqueRequest is the request torque for controlling the rear wheel drive motor for a new round.
According to the technical scheme, the required torque of the rear wheel driving motor can be accurately calculated after the rear wheel driving motor is reduced every time, so that the actual slip rate is controlled to be reduced until the magnitude relation between the target slip rate and the actual slip rate meets the preset drift condition, and the risk of controlling the vehicle to be out of control by a driver is reduced.
Optionally, fig. 3 is a flowchart for implementing step S13 in fig. 1 according to an exemplary embodiment, and referring to fig. 3, in step S13, if the reference vehicle speed is less than a preset vehicle speed threshold, limiting the requested torque of the rear wheel drive motor according to the reference maximum torque includes:
In step S131, if the reference vehicle speed is smaller than the preset vehicle speed threshold, the reference maximum torque is determined according to the ground attachment coefficient, the mass of the whole vehicle and the rolling radius of the vehicle tyre.
In the embodiment of the disclosure, the reference maximum torque may be calculated by the following formula:
TorqueMax= Mue×m×g×r+Offset
wherein torquermax is the reference maximum torque, mue is the ground attachment coefficient, m is the mass of the whole vehicle, wherein the mass of the whole vehicle can be the full load mass of the vehicle, g is the gravitational acceleration, r is the rolling radius of the vehicle tyre, and Offset is the standard quantity.
Wherein the maximum value MuMax of the road adhesion coefficient Mue is 1, and the ground use adhesion coefficient muused=Ax and ay are longitudinal acceleration and transverse acceleration read by an inertial measurement sensor, and g is gravitational acceleration.
And under the condition that the difference between the first vehicle speed calculated according to the average value of the wheel speeds of the rear wheels and the reference vehicle speed is larger than a preset difference threshold value, the road adhesion coefficient Mue =min (MuMax, muused), and under the condition that the difference between the first vehicle speed and the reference vehicle speed is smaller than or equal to the preset difference threshold value, the road adhesion coefficient Mue =MuMax.
In step S132, in the case where the requested torque of the rear wheel drive motor is greater than the reference maximum torque, the requested torque of the rear wheel drive motor of the vehicle is limited with the reference maximum torque.
It is noted that, in the case where the requested torque of the rear wheel drive motor is greater than the reference maximum torque, the rear wheel drive motor is controlled with the reference maximum torque as the requested torque of the rear wheel drive motor of the vehicle. In the case where the requested torque of the rear wheel drive motor is equal to or less than the reference maximum torque, the rear wheel drive motor is controlled with the requested torque of the rear wheel drive motor.
According to the technical scheme, when the request torque of the rear wheel driving motor is larger than the reference maximum torque, the reference maximum torque is used for controlling the rear wheel driving motor. Therefore, the problem that the vehicle is turned over and the safety of the vehicle is affected due to the fact that the tail of the vehicle is thrown out of control due to the fact that the throttle input is too large is avoided.
Optionally, the drift parameter value includes a front wheel speed, and determining the reference vehicle speed of the vehicle according to the drift parameter value includes:
and determining the reference speed of the vehicle according to the average value of the front wheel speeds.
It can be stated that, for a four-wheel drive vehicle type, the vehicle realizes the precondition of drifting that the front wheel drive motor outputs a smaller torque or no torque output. In the drifting process, the front wheels cannot slip, and the rear wheels slip and drift due to the output torque of the rear wheel driving motor. Therefore, the wheel speeds of the left and right front wheels are close to the true vehicle speed, and the wheel speeds of the left and right rear wheels are not reliable. And the numerical value of the average value of the wheel speeds of the front wheels can be converted to obtain the reference speed of the vehicle.
Optionally, referring to fig. 4, the vehicle drift control method includes:
in step S41, if it is determined that the vehicle is out of control during the vehicle drift, the target body slip angle and the braking force coefficient of the vehicle are determined based on the reference vehicle speed.
The map table of the reference vehicle speed and the braking force coefficient can be established in advance, and the braking force coefficient is obtained through inquiring the reference vehicle speed. The braking force coefficient is positively correlated with the reference vehicle speed, namely the larger the reference vehicle speed is, the larger the braking force coefficient is; the smaller the reference vehicle speed, the smaller the braking force coefficient.
The mapping relation table of the reference vehicle speed and the vehicle body slip angle can be established in advance, and then the target vehicle body slip angle is obtained through reference vehicle speed inquiry.
In step S42, a target braking force is determined based on the braking force coefficient, the difference between the target vehicle body slip angle and the current vehicle body slip angle.
In the embodiment of the present disclosure, the target braking force is determined by the following calculation formula:
BrakeTqReq=q×△β
wherein BraketqReq is a target braking force, q is a braking force coefficient, and Deltaβ is a difference between a target vehicle body slip angle and a current vehicle body slip angle of the vehicle.
In step S43, a target braking force is applied to a target wheel of the vehicle, which is a front wheel of the vehicle on the outside in the drifting direction and a rear wheel on the outside in the drifting direction, until the current body slip angle of the vehicle is equal to or smaller than the target body slip angle.
In the embodiment of the disclosure, the drifting direction may be a direction in which the vehicle tail slides, for example, the vehicle tail slides rightward relative to the vehicle head, and then the drifting direction is rightward, and then the front wheels outside the drifting direction and the rear wheels outside the drifting direction may be the front right wheel and the rear right wheel of the vehicle; the vehicle tail slides leftwards relative to the vehicle head, the drifting direction is leftwards, and then the front wheels outside the drifting direction and the rear wheels outside the drifting direction can be the left front wheels and the left rear wheels of the vehicle.
In the drifting process of the vehicle, the road surface friction force is possibly changed, so that the vehicle slip angle is suddenly increased, a driver is in a panic state, and the steering wheel is reversely hit for rescuing the vehicle, at the moment, the drifting is determined to be out of control, and according to the difference value of the current vehicle body slip angle and the target slip angle, the target braking force is calculated and sent to a braking system to perform target wheel braking control, so that the vehicle body posture is corrected, and the vehicle is controlled.
According to the technical scheme, the front wheels positioned on the outer side of the drifting direction and the rear wheels positioned on the outer side of the drifting direction are simultaneously applied with the target braking force, so that the current body slip angle of the vehicle can be quickly reduced to the target body slip angle, the body posture can be quickly corrected, and the vehicle is prevented from turning on one's side in the drifting process.
Alternatively, the occurrence of drift runaway in the vehicle is determined by:
the current body slip angle of the vehicle body is obtained.
In the embodiment of the disclosure, the current vehicle body slip angle of the vehicle body may be calculated according to accelerations in multiple directions measured by the inertia measurement unit and centroid speeds of front wheels and rear wheels of the vehicle relative to a centroid of the vehicle based on the prior art. And therefore will not be described in detail herein.
And inquiring from a vehicle body slip angle mapping table according to the reference vehicle speed to obtain a target vehicle body limit slip angle, wherein the vehicle body limit slip angle mapping table stores the vehicle body limit slip angle corresponding to each reference vehicle speed.
The vehicle body limit slip angle mapping table of the reference vehicle speed and the vehicle body limit slip angle can be established in advance, and then the target vehicle body limit slip angle is obtained through reference vehicle speed inquiry. In the vehicle body slip angle mapping table, the vehicle body limit slip angle is positively correlated with the reference vehicle speed, namely, the larger the reference vehicle speed is, the larger the vehicle body limit slip angle is; the smaller the reference vehicle speed, the smaller the vehicle body limit slip angle.
And under the condition that the current body slip angle of the vehicle body is larger than the target body limit slip angle, determining that the vehicle is out of control in drift.
It can be stated that the fact that the current vehicle body slip angle of the vehicle body is larger than the target vehicle body limit slip angle indicates that the risk of vehicle drifting and rollover is larger under the current vehicle speed of the vehicle, and the fact that the vehicle has drifting out of control can be determined.
Alternatively, the occurrence of drift runaway in the vehicle is determined by:
the current rotation direction and the rotation angle of the steering wheel of the vehicle are obtained.
The current rotation direction and rotation angle of the steering wheel can be obtained through a sensor on the steering column. The current rotation direction and rotation angle of the steering wheel of the vehicle can be obtained through the rotation direction and rotation angle of the steering wheel.
And under the condition that the rotation direction is inconsistent with the drift direction, determining the current steering wheel limit rotation angle of the vehicle.
The mapping table of the reference vehicle speed and the steering wheel limit turning angle can be established in advance, and the steering wheel limit turning angle is obtained through reference vehicle speed inquiry.
And under the condition that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift.
If the difference between the steering wheel limit turning angle and the turning angle is in the preset difference range, the current turning angle of the steering wheel is about to reach the steering wheel limit turning angle, the yaw rate of the vehicle is continuously increased, and the risk of vehicle rollover is higher, so that the vehicle is determined to have drift out of control.
The yaw rate may be determined based on the wheel speed of the outside wheel in the vehicle drift direction, the wheel speed of the inside wheel in the vehicle drift direction, the wheel track, and the current rotation angle of the steering wheel, for example, yaw rate= (wheel speed of the outside wheel-wheel speed of the inside wheel)/wheel track×cos current rotation angle of the steering wheel.
Optionally, the vehicle drift control method includes:
driver monitoring information is obtained from a driver monitoring system.
The driver monitoring system can acquire image information of a driver through a camera arranged in the vehicle, and further analyze the image information to obtain driver monitoring information.
Under the condition that the difference value between the steering wheel limit rotation angle and the rotation angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift comprises the following steps:
and determining that the vehicle has out of control drift under the conditions that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range, the yaw rate of the vehicle is continuously increased and the driver monitoring information indicates that the driver is in a driving confusion state.
It may be noted that if the driver monitoring information indicates that the driver is in a driving confusion state, for example, the driver turns the hand of the steering wheel to be in a confusion state, or the driver is in an expression confusion state, the driver can be determined to be in the driving confusion state. The driver being in a panic state indicates a high risk of vehicle drift out of control.
Fig. 5 is a schematic view showing a vehicle drift according to an exemplary embodiment, referring to fig. 5, in a case where the vehicle is in a vehicle drift mode, a signal processing unit acquires sensor signals of sensors such as an inertial measurement sensor, a wheel speed sensor, and the like, and performs signal processing such as filtering, coordinate conversion, and the like on the sensor signals to obtain yaw rate Yawrate, and current rotation information SAS of the steering wheel, wherein the rotation information SAS includes a rotation direction and a rotation angle, and a driver monitoring system DMS (driver monitoring system) acquires image information acquired by a camera from the camera, the image information referring to image information of the driver, such as facial image information or hand image information.
Further, the estimation unit estimates a vehicle body slip angle actβ, a reference vehicle speed Vref, and a ground attachment coefficient Mue, and the first drift control unit determines a requested torque MotorTqReq of the rear wheel drive motor according to the reference vehicle speed Vref, the ground attachment coefficient Mue, and the rear wheel speed RearSpd, and the rear wheel drive motor outputs a driving force reartright to the rear wheels according to the requested torque MotorTqReq.
Further, the vehicle body lateral deviation monitoring unit determines whether the vehicle is out of control in a drifting manner according to the yaw rate Yawrate, the current rotation information SAS of the steering wheel and the vehicle body lateral deviation angle actβ, generates a drifting-out-of-control signal Spinobs when the vehicle is determined to be out of control in a drifting manner, and further calculates a target braking force BrakeTqReq under the condition that the second drifting control unit receives the drifting-out-of-control signal Spinobs, and the braking system applies a braking force brakettorque to the target wheels according to the target braking force BrakeTqReq until the vehicle is determined not to be out of control in a drifting manner.
The embodiment of the present disclosure also provides a vehicle drift control device, fig. 6 is a block diagram of a vehicle drift control device according to an exemplary embodiment, and referring to fig. 6, the vehicle drift control device includes: the acquisition module 510, the first determination module 520, the second determination module 530, and the control module 540.
Wherein the obtaining module 510 is configured to obtain a drift parameter value of the vehicle in case the vehicle is in a vehicle drift mode;
the first determination module 520 is configured to determine a reference vehicle speed of the vehicle based on the drift parameter value;
the second determination module 530 is configured to limit the requested torque of the rear wheel drive motor according to the reference maximum torque if the reference vehicle speed is less than the preset vehicle speed threshold; if the reference vehicle speed is greater than or equal to a preset vehicle speed threshold value, determining the required torque of the rear wheel driving motor according to the slip rate;
the control module 540 is configured to torque control the rear wheel drive motor in accordance with the requested torque to enable vehicle drift.
Optionally, the slip ratio includes a target slip ratio and an actual slip ratio, and the second determining module 530 is configured to:
if the reference vehicle speed is greater than or equal to a preset vehicle speed threshold value, inquiring to obtain a target slip rate according to the reference vehicle speed;
Determining an actual slip rate according to the reference vehicle speed and the rear wheel speed in the drift parameter value;
and under the condition that the magnitude relation between the target slip rate and the actual slip rate does not meet the preset drift condition, reducing the request torque of the rear wheel driving motor of the vehicle until the magnitude relation between the target slip rate and the actual slip rate meets the preset drift condition.
Optionally, the second determining module 530 is configured to:
under the condition that the magnitude relation between the target slip rate and the actual slip rate does not meet the preset drift condition, determining a slip rate difference value between the actual slip rate and the target slip rate;
determining a torque reduction gradient according to a preset proportion coefficient and a slip ratio difference value;
and reducing the request torque of the rear wheel drive motor according to the torque reduction gradient and the current output torque of the rear wheel drive motor.
Optionally, the second determining module 530 is configured to:
if the reference vehicle speed is smaller than the preset vehicle speed threshold value, determining a reference maximum torque according to the ground attachment coefficient, the whole vehicle mass and the rolling radius of the vehicle tyre;
in the case where the requested torque of the rear wheel drive motor is greater than the reference maximum torque, the requested torque of the rear wheel drive motor of the vehicle is limited with the reference maximum torque.
Optionally, the drift parameter value includes a front wheel speed, and the first determining module 520 is configured to:
and determining the reference speed of the vehicle according to the average value of the front wheel speeds.
Optionally, the vehicle drift control device includes: a runaway control module configured to:
if the vehicle is determined to have drift out of control in the vehicle drifting process, determining a target vehicle body slip angle and a braking force coefficient of the vehicle according to a reference vehicle speed;
determining a target braking force according to the braking force coefficient and the difference value of the target vehicle body slip angle and the current vehicle body slip angle of the vehicle;
and applying a target braking force to a target wheel of the vehicle until a current body slip angle of the vehicle is equal to or less than the target body slip angle, wherein the target wheel is a front wheel of the vehicle outside the drifting direction and a rear wheel of the vehicle outside the drifting direction.
Optionally, the runaway control module is configured to determine that the vehicle is out of drift by:
acquiring the current body side deflection angle of a vehicle body;
inquiring a target vehicle body limit slip angle from a vehicle body slip angle mapping table according to the reference vehicle speed, wherein the vehicle body limit slip angle corresponding to each reference vehicle speed is stored in the vehicle body slip angle mapping table;
And under the condition that the current body slip angle of the vehicle body is larger than the target body limit slip angle, determining that the vehicle is out of control in drift.
Optionally, the runaway control module is configured to determine that the vehicle is out of drift by:
acquiring the current rotation direction and rotation angle of a steering wheel of a vehicle;
under the condition that the rotation direction is inconsistent with the drift direction, determining the current steering wheel limit rotation angle of the vehicle;
and under the condition that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift.
Optionally, the vehicle drift control device includes: a second acquisition module configured to acquire driver monitoring information from the driver monitoring system;
the control module is used for controlling the steering wheel to rotate, and the control module is used for controlling the steering wheel to rotate according to the steering angle of the steering wheel.
With respect to the vehicle drift control device in the above-described embodiment, the specific manner in which the respective modules perform the operations has been described in detail in the embodiment regarding the method, and will not be explained in detail here.
The disclosed embodiments also provide a vehicle including:
a first processor;
a first memory for storing first processor-executable instructions;
wherein the first processor is configured to execute the executable instructions stored in the first memory to implement any one of the vehicle drift control methods of the previous embodiments.
Embodiments of the present disclosure provide a computer-readable storage medium having stored thereon computer program instructions which, when executed by a second processor, implement the steps of the vehicle drift control method of any of the preceding embodiments.
Fig. 7 is a block diagram of a vehicle 600, according to an exemplary embodiment. For example, the vehicle 600 may be a hybrid vehicle, but may also be a pure electric vehicle, a fuel cell vehicle, or another type of vehicle. The vehicle 600 may be an autonomous vehicle, a semi-autonomous vehicle, or a non-autonomous vehicle.
Referring to fig. 7, a vehicle 600 may include various subsystems, such as an infotainment system 610, a perception system 620, a decision control system 630, a drive system 640, and a computing platform 650. Wherein the vehicle 600 may also include more or fewer subsystems, and each subsystem may include multiple components. In addition, interconnections between each subsystem and between each component of the vehicle 600 may be achieved by wired or wireless means.
In some embodiments, the infotainment system 610 may include a communication system, an entertainment system, a navigation system, and the like.
The perception system 620 may include several sensors for sensing information of the environment surrounding the vehicle 600. For example, the sensing system 620 may include a global positioning system (which may be a GPS system, a beidou system, or other positioning system), an inertial measurement unit (inertial measurement unit, IMU), a lidar, millimeter wave radar, an ultrasonic radar, and a camera device.
Decision control system 630 may include a computing system, a vehicle controller, a steering system, a throttle, and a braking system.
The drive system 640 may include components that provide powered movement of the vehicle 600. In one embodiment, the drive system 640 may include an engine, an energy source, a transmission, and wheels. The engine may be one or a combination of an internal combustion engine, an electric motor, an air compression engine. The engine is capable of converting energy provided by the energy source into mechanical energy.
Some or all of the functions of the vehicle 600 are controlled by the computing platform 650. The computing platform 650 may include at least one third processor 651 and a third memory 652, the third processor 651 may execute instructions 653 stored in the third memory 652.
The third processor 651 may be any conventional processor, such as a commercially available CPU. The processor may also include, for example, an image processor (Graphic Process Unit, GPU), a field programmable gate array (Field Programmable Gate Array, FPGA), a System On Chip (SOC), an application specific integrated Chip (Application Specific Integrated Circuit, ASIC), or a combination thereof.
The third memory 652 may be implemented by any type or combination of volatile or nonvolatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disk.
In addition to the instructions 653, the third memory 652 may store data such as road map, route information, position, direction, speed, etc. of the vehicle. The data stored by the third memory 652 may be used by the computing platform 650.
In an embodiment of the present disclosure, the third processor 651 may execute the instructions 653 to complete all or part of the steps of the vehicle drift control method described above.
Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.
It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims (12)

1. A vehicle drift control method, characterized by comprising:
under the condition that the vehicle is in a vehicle drifting mode, acquiring a drifting parameter value of the vehicle;
determining a reference vehicle speed of the vehicle according to the drift parameter value;
if the reference vehicle speed is smaller than a preset vehicle speed threshold value, limiting the request torque of the rear wheel driving motor according to the reference maximum torque;
if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, determining the request torque of the rear wheel driving motor according to the slip rate;
And controlling the torque of the rear wheel drive motor according to the request torque so as to enable the vehicle to drift.
2. The vehicle drift control method according to claim 1, characterized in that the slip ratio includes a target slip ratio and an actual slip ratio, and the determining the requested torque of the rear wheel drive motor according to the slip ratio if the reference vehicle speed is equal to or greater than the preset vehicle speed threshold value includes:
if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, inquiring to obtain the target slip rate according to the reference vehicle speed;
determining the actual slip rate according to the reference vehicle speed and the rear wheel speed in the drift parameter value;
and under the condition that the magnitude relation between the target slip rate and the actual slip rate does not meet a preset drift condition, reducing the request torque of a rear wheel driving motor of the vehicle until the magnitude relation between the target slip rate and the actual slip rate meets the preset drift condition.
3. The vehicle drift control method according to claim 2, characterized in that the reducing the requested torque of the rear wheel drive motor of the vehicle in the case where it is determined that the magnitude relation of the target slip ratio and the actual slip ratio does not satisfy a preset drift condition, includes:
Determining a slip ratio difference value between the actual slip ratio and the target slip ratio under the condition that the magnitude relation between the target slip ratio and the actual slip ratio does not meet a preset drift condition;
determining a torque reduction gradient according to a preset proportionality coefficient and the slip ratio difference value;
and reducing the request torque of the rear wheel driving motor according to the torque reduction gradient and the current output torque of the rear wheel driving motor.
4. The vehicle drift control method according to claim 1, characterized in that if the reference vehicle speed is smaller than a preset vehicle speed threshold value, limiting the requested torque of the rear wheel drive motor according to the reference maximum torque includes:
if the reference vehicle speed is smaller than a preset vehicle speed threshold value, determining a reference maximum torque according to a ground attachment coefficient, the whole vehicle mass and the rolling radius of the vehicle tyre;
in the case where the requested torque of the rear wheel drive motor is greater than the reference maximum torque, the requested torque of the rear wheel drive motor of the vehicle is limited with the reference maximum torque.
5. The vehicle drift control method according to claim 1, characterized in that the drift parameter value includes a front wheel speed, and the determining the reference vehicle speed of the vehicle from the drift parameter value includes:
And determining the reference speed of the vehicle according to the average value of the front wheel speeds.
6. The vehicle drift control method according to any one of claims 1 to 5, characterized in that the vehicle drift control method includes:
if the vehicle is determined to have drift out of control in the vehicle drifting process, determining a target vehicle body slip angle and a braking force coefficient of the vehicle according to the reference vehicle speed;
determining a target braking force according to the braking force coefficient, the difference value of the target vehicle body slip angle and the current vehicle body slip angle of the vehicle;
and applying the target braking force to a target wheel of the vehicle until the current body slip angle of the vehicle is less than or equal to the target body slip angle, wherein the target wheel is a front wheel of the vehicle which is positioned outside a drifting direction and a rear wheel which is positioned outside the drifting direction.
7. The vehicle drift control method according to claim 6, characterized in that the occurrence of drift runaway of the vehicle is determined by:
acquiring a current body slip angle of the vehicle body;
inquiring a target vehicle body limit slip angle from a vehicle body slip angle mapping table according to the reference vehicle speed, wherein the vehicle body limit slip angle corresponding to each reference vehicle speed is stored in the vehicle body slip angle mapping table;
And under the condition that the current body slip angle of the vehicle body is larger than the target body limit slip angle, determining that the vehicle is out of control in drift.
8. The vehicle drift control method according to claim 6, characterized in that the occurrence of drift runaway of the vehicle is determined by:
acquiring the current rotation direction and rotation angle of the steering wheel of the vehicle;
determining a current steering wheel limit angle of the vehicle under the condition that the rotation direction is inconsistent with the drifting direction;
and under the condition that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift.
9. The vehicle drift control method according to claim 8, characterized in that the vehicle drift control method includes:
acquiring driver monitoring information from a driver monitoring system;
and under the condition that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range and the yaw rate of the vehicle is continuously increased, determining that the vehicle is out of control in drift, comprising the following steps:
And determining that the vehicle is out of control in drift under the conditions that the difference value between the steering wheel limit turning angle and the turning angle is in a preset difference value range, the yaw rate of the vehicle is continuously increased, and the driver monitoring information indicates that the driver is in a driving confusion state.
10. A vehicle drift control device, characterized by comprising:
an acquisition module configured to acquire a drift parameter value of the vehicle in a case where the vehicle is in a vehicle drift mode;
a first determination module configured to determine a reference vehicle speed of the vehicle based on the drift parameter value;
a second determining module configured to limit the requested torque of the rear wheel drive motor according to the reference maximum torque if the reference vehicle speed is less than a preset vehicle speed threshold; if the reference vehicle speed is greater than or equal to the preset vehicle speed threshold value, determining the request torque of the rear wheel driving motor according to the slip rate;
a control module configured to torque control the rear wheel drive motor in accordance with the requested torque to enable the vehicle to drift.
11. A vehicle, characterized by comprising:
a processor;
a memory for storing processor-executable instructions;
Wherein the processor is configured to execute the executable instructions stored by the memory to implement the vehicle drift control method of any one of claims 1-9.
12. A computer readable storage medium having stored thereon computer program instructions, which when executed by a processor, implement the steps of the vehicle drift control method of any of claims 1-9.
CN202310923166.XA 2023-07-25 2023-07-25 Vehicle drift control method and device, vehicle and medium Active CN116674556B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310923166.XA CN116674556B (en) 2023-07-25 2023-07-25 Vehicle drift control method and device, vehicle and medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310923166.XA CN116674556B (en) 2023-07-25 2023-07-25 Vehicle drift control method and device, vehicle and medium

Publications (2)

Publication Number Publication Date
CN116674556A CN116674556A (en) 2023-09-01
CN116674556B true CN116674556B (en) 2023-10-31

Family

ID=87782197

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310923166.XA Active CN116674556B (en) 2023-07-25 2023-07-25 Vehicle drift control method and device, vehicle and medium

Country Status (1)

Country Link
CN (1) CN116674556B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001082201A (en) * 1999-09-13 2001-03-27 Toyota Motor Corp Behavior control device for vehicle
CN114954394A (en) * 2021-07-21 2022-08-30 长城汽车股份有限公司 Vehicle drift control method and system and vehicle
CN115042758A (en) * 2022-05-16 2022-09-13 中国第一汽车股份有限公司 Control method and control device for vehicle drifting working condition
CN116238479A (en) * 2023-02-28 2023-06-09 东风汽车有限公司东风日产乘用车公司 Vehicle drift control method, device, equipment and storage medium

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11858497B2 (en) * 2021-06-14 2024-01-02 Toyota Research Institute, Inc. Operator drift maintenance
KR20230045384A (en) * 2021-09-28 2023-04-04 현대자동차주식회사 Electric vehicle drift control system and method therefor

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001082201A (en) * 1999-09-13 2001-03-27 Toyota Motor Corp Behavior control device for vehicle
CN114954394A (en) * 2021-07-21 2022-08-30 长城汽车股份有限公司 Vehicle drift control method and system and vehicle
CN115042758A (en) * 2022-05-16 2022-09-13 中国第一汽车股份有限公司 Control method and control device for vehicle drifting working condition
CN116238479A (en) * 2023-02-28 2023-06-09 东风汽车有限公司东风日产乘用车公司 Vehicle drift control method, device, equipment and storage medium

Also Published As

Publication number Publication date
CN116674556A (en) 2023-09-01

Similar Documents

Publication Publication Date Title
US11091164B2 (en) Method and system for computing a road friction estimate
JP4161923B2 (en) Vehicle stabilization control system
US8775048B2 (en) Method and apparatus for determining a reference vehicle velocity and a rear wheel speed in a vehicle having three speed sensors
US9662974B2 (en) Torque control for vehicles with independent front and rear propulsion systems
JP4752819B2 (en) Vehicle travel control device
US6862512B2 (en) Method and system for controlling the performance of a motor vehicle
JP5341469B2 (en) Vehicle control device
US20210229667A1 (en) Vehicle control apparatus and vehicle control method
CN114787014A (en) On-board road friction estimation
CN108860137B (en) Control method and device for unstable vehicle and intelligent vehicle
CN116513191B (en) Vehicle driving anti-skid method and device, vehicle and storage medium
CN112339744B (en) Method for controlling wheel slip of vehicle
EP4378729A1 (en) Vehicle drift control method and apparatus, vehicle, storage medium and chip
GB2435102A (en) Friction estimation for vehicle control systems
CN116674556B (en) Vehicle drift control method and device, vehicle and medium
JP3271956B2 (en) Road surface friction coefficient estimation device for vehicles
JP4928221B2 (en) Vehicle behavior control device
CN115027492A (en) Target vehicle state identification for autopilot adaptation in vehicle control
WO2010016108A1 (en) Vehicle travel controller
US20230219562A1 (en) Driving force control apparatus, system including the same, and method thereof
CN113276834B (en) System and method for vehicle integrated stability control using a perceived yaw center
JP2019098753A (en) Self-driving device and self-driving method
US20240182108A1 (en) Vehicle drift control method and apparatus, vehicle, storage medium and chip
JP7354272B2 (en) Method for estimating vehicle motion state during vehicle operation
US20230202461A1 (en) Device for distributing driving force, system including the same, and operation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant